Axle assembly

ABSTRACT

An axle assembly is supplied capable of solving that troublesome mounting and dismantling works needing a wrench to screw fasten bolt. In the axle assembly, the present invention is to furnish nipping and holding member with collet shape on tubular body; to insert the nipping and holding member into penetrating hole of shaft mounting portion so as to shrink diameter; and to directly insert the tubular body into the penetrating hole. When moving fastening bar by operation of cam lever, both nipping and holding members nip and hold the shaft mounting portion. While dismantling, diameter shrinking part moves so as to make the nipping and holding member shrink diameter.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an axle assembly to mount wheel hub ofa bicycle to front fork or suspension fork.

2. Related Background Art

Conventional axle assembly has a tubular body and a pair of nipping andholding members with flange shape. In the conventional axle assembly,through inserting both ends of the tubular body into respectivepenetrating holes of a pair of shaft mounting portions (i.e. dropouts)furnished below a suspension fork; screwing the respective nipping andholding members into the both ends of the tubular body; and using thenipping and holding members to nip and hold the pair of shaft mountingportions, the tubular boby is installed on the pair of the shaftmounting portions. The tubular body rotatably supports a hub of wheel.

The shaft mounting portions to mount such conventional axle assembly areformed into two separate structures in order to enable to shrinkdiameter of the penetrating holes of the shaft mounting portions. Afterinserted the tubular body into the penetrating hole, through integratingthem by tightness of fastening bolt so as to shrink diameter of thepenetrating hole, the tubular body is fixed strongly.

However, as stated above, when screwing the nipping and holding memberor performing the tightness of the fastening bolt, there is a problemthat: not only a wrench is needed, but also time and exertion are neededfor mounting and dismantling works of the tubular body.

Recently, through furnishing throat for expanding diameter at both endsof the tubular body; moving a fastening bar furnished on the tubularbody by a lever operation of a cam lever; expanding diameters of theboth ends of the tubular body via the throats by pressing a taper washerconnected to the fastening bar into the both ends of the tubular body;and squeezing peripheral surfaces of the both ends of the tubular bodyonto wall surfaces of the penetrating holes of the shaft mountingportions, the axle assembly having a structure in which the tubular bodyis installed on the shaft mounting portion is used practically.

This axle assembly can dismantle the tubular body from the shaftmounting portions through restoring the cam lever to an open positionand taking off the taper washer from the fastening bar, and it hascomparatively simple structure for mounting and dismantling. However,since there are throats at both ends of the tubular body, there is adrawback that the strength of the tubular body becomes weak.

SUMMARY OF THE INVENTION

It is, therefore, an objective of the invention to provide an axleassembly capable of solving the above problem. That is, the presentinvention has an objective to provide an axle assembly which enables tosimply perform mounting and dismantling works with respect to shaftmounting portions and has excellent mechanical strength.

According to the present invention, there is provided an axle assemblyhaving a tubular body whose both ends are inserted into respectivepenetrating holes formed on a pair of shaft mounting portions, androtatably supports wheel hub, comprising:

a nipping and holding means that is installed on one end of the tubularbody and is used for pressing edge of the penetrating hole of the shaftmounting portion on one side;

a fastening bar that passes through the nipping and holding means and isplaced inside the tubular body;

a moving means that is placed to face to the nipping and holding means,is connected to one end of the fastening bar, and makes the fasteningbar move inside the tubular body towards one end of the tubular body;

a nipping and holding means with collet shape that has plural partitionpieces and protrudes from other end of the tubular body so as to makethe plural partition pieces can expand and shrink diameter;

a pressing means that is connected to other end of the fastening bar,presses the nipping and holding means with collet shape by movement ofthe fastening bar, and presses the respective partition pieces to edgeof the penetrating hole of the shaft mounting portion on the other side;and

a diameter shrinking means that is installed on the pressing means so asto enable to move towards the other end of the tubular body, and coupleswith the plural partition pieces by moving so as to shrink diameter.

3. Effect of the Present Invention

According to the present invention, because the nipping and holdingmember with collet shape contacts to the wall surface of the penetratinghole of the shaft mounting portion and shrinks diameter, the tubularbody and the nipping and holding member can be directly inserted intothe penetrating hole. In addition, through shrinking diameter of thenipping and holding member with collet shape by a moving operation ofthe diameter shrinking means, the tubular body can be taken off from thepenetrating holes. Therefore, it is possible to perform the installingand dismantling works simply. In addition, according to the presentinvention, because the pair of shaft mounting portions are nipped andheld by two nipping and holding members without designing throats on thetubular body, the strength of installation is improved.

The above and other objects and features of the present invention willbecome apparent from the following detailed description and the appendedclaims with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of an axle assembly related to the presentinvention;

FIG. 2 is a disassembled oblique view of an axle assembly;

FIG. 3A to FIG. 3C are sectional views for explaining mounting of thisassembly onto shaft mounting portion and its movement;

FIG. 4A to FIG. 4C are diagrams for explaining dismantling of thisassembly from the shaft mounting portion and its movement;

FIG. 5 is a sectional view related to transformation embodiment of anaxle assembly of the present invention; and

FIG. 6 is an oblique view of fork structure related to the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment

Embodiments of the invention will be described in detail hereinbelowwith reference to the drawings.

FIG. 6 is an oblique view of fork structure installing an axle assembly10 related to the present invention.

In FIG. 6, 1 shows front fork, on the front fork 1, a suspension fork 2with reverse U-shape is installed. On lower portions of respective forksof the suspension fork 2, shaft mounting portions 3A and 3B are mounted.On the shaft mounting portions 3A and 3B, a penetrating hole 4 isrespectively formed. An axle assembly 10 of the present invention ispassed through the penetrating hole 4 of the shaft mounting portion 3Aon one side and is inserted into and passed through hub 5, further, ispassed though the penetrating hole 4 of the shaft mounting portion 3B onthe other side.

FIG. 1 is a sectional view of the axle assembly 10 in the presentinvention, and FIG. 2 is a disassembled oblique view of the axleassembly 10.

The axle assembly 10 has a tubular body 11 as shown in FIG. 1 and FIG.2. A nipping and holding member 12 is screwed into an opening of one endof the tubular body 11. The nipping and holding member 12 has a tubularscrewed part 12 a and a flange part 12 b which is protruded towards theradial direction while closing the opening. A sliding and contacting useplate 13 is fit to a concave of the flange part 12 b.

The sliding and contacting use plate 13 is made from plastic, it is usedto enable a cam lever 14 to slide smoothly. The cam lever 14 is composedof a cam part 14 a and a lever 14 b. The cam part 14 a has a camshaft 15eccentrically arranged. One end of a fastening bar 16 is inserted intothe camshaft 15 and is fixed. The fastening bar 16 goes through thesliding and contacting use plate 13 and the screwed part 12 a of thenipping and holding member 12, and is coaxially arranged inside thetubular body 11. Other end of the fastening bar 16 is protruded from thetubular body 11. A screw slot 16 a is furnished on the other end of thefastening bar 16.

The inner wall of other end of the tubular body 11 is formed with aslight thickness through a recess section. One end of coil spring 17 iscontacted with the recess section. A cylindrical guide block 18 ispressed on other end of the coil spring 17. As shown in FIG. 2, on theguide block 18, six strips of guide grooves 18 a radiating along radiusdirection are formed.

The guide groove 18 a of the guide block 18 is used to expand or shrinkdiameter of the nipping and holding member 19 with collet shape. Thatis, the nipping and holding member 19 is composed of six partitionpieces 19 a that protrude from the other end of the tubular body 11 andare arranged in concentric arrangement. Each partition piece 19 aincludes a flange part 20 having slant surface 20 a, and a protuberance19 b fitting to the guide groove 18 a.

A pressing member 21 is arranged to face to the nipping and holdingmember 19 with collet shape. The pressing member 21 is screwed with thescrew slot 16 a of the fastening bar 16, and is composed of a taper part21 a and a serration shaft 21 b for pressing respective inside slantsurfaces 20 b of plural partition pieces 19 a.

A tubular shrinking member 22 is mounted on the pressing member 21. Theshrinking member 22 is fit to the pressing member 21 so as to be able tomove towards the nipping and holding member 19. An inside taper surface22 a is formed at front end of the shrinking member 22 for pressingrespective slant surfaces 20 a on the flange parts 20 of the pluralpartition pieces 19 a. A serration boss 23 is screwed into rear end ofthe shrinking member 22. The serration boss 23 is movably fit to theserration shaft 21 b so as to allow the shrinking member 22 to move.

In the axle assembly 10 of the present invention having theabove-mentioned structure, as shown in FIG. 1, when the cam lever 14locates in the open position, the nipping and holding member 19 withcollet shape leaves one of the nipping and holding members 12.

Next, the operation of the axle assembly 10 in the present inventionwill be explained together with usage pattern.

FIG. 3A to FIG. 3C are sectional views for explaining mounting order ofthe axle assembly 10.

Firstly, as shown in FIG. 3A, the axle assembly 10 is inserted into thepenetrating hole 4 of the shaft mounting portion 3A from the side of theshrinking member 22, and is sequentially inserted into a hub 5 and theshaft mounting portion 3B. During the aforesaid inserting work, in thenipping and holding member 19 with collet shape, the slant surfaces 20 aof the flange parts 20 of the partition pieces 19 a slidably contactwith the inner wall surface of the penetrating hole 4 and with the innerwall surface of the hub 5, the respective partition pieces 19 a areguided towards the guide grooves 18 a of the guide block 18 and approacheach other. That is, because the nipping and holding member 19automatically shrinks diameter, it is possible to make the axle assembly10 pass through the both penetrating holes 4 and the hub 5 only bypushing and pressing the axle assembly 10.

Next, as shown in FIG. 3B, when the axle assembly 10 is pushed andpressed, the flange part 12 b of the nipping and holding members 12 onone side contacts with the edge of a penetrating hole of the shaftmounting portion 3A, and it becomes impossible to push and press. Insuch pushing and pressing state, the flange part 20 of the nipping andholding member 19 with collet shape on the other side is protruded fromthe shaft mounting portion 3B, and the respective partition pieces 19 aare kept in diameter expansion state.

Next, as shown in FIG. 3C, the cam lever 14 is performed to rotatedownward. By the operation, because the cam part 14 a slidably contactswith the sliding and contacting use plate 13 while rotating; and thecamshaft 15 separates from the sliding and contacting use plate 13, thefastening bar 16 axially moves only the separate distance. Accordingly,because the pressing member 21 also moves and presses the nipping andholding member 19 with collet shape due to the taper part 21 a, thenipping and holding member 19 (plural partition pieces 19 a) movesagainst resilience of the coil spring 17 while expanding diameter.Therefore, because the flange part 20 of the nipping and holding member19 is pressed to the edge of the penetrating hole 4 of the shaftmounting portion 3B, the axle assembly 10 of the present invention canbe mounted onto the suspension fork 2.

Next, dismantling work of the axle assembly 10 of the present inventionwill be explained by referring to FIG. 4.

Firstly, as shown in FIG. 4A, the cam lever 14 is performed to rotateupward. By the operation, the flange part 20 of the nipping and holdingmember 19 with collet shape releases to nip and hold the shaft mountingportion 3B. In the case, because the nipping and holding member 19 iskept in a diameter expansion state, the nipping and holding member 19 isunable to pass through the penetrating hole 4.

Next, as shown in FIG. 4B, the shrinking member 22 is moved leftward asshown in the diagram. By the operation, because the inner taper surface22 a of the shrinking member 22 presses the slant surfaces 20 a in theflange part 20 of each partition piece 19 a of the nipping and holdingmember 19, the respective partition pieces 19 a approach each other soas to shrink diameter. Accordingly, because it become possible to makethe nipping and holding member 19 pass through the penetrating hole 4 ofthe shaft mounting portion 3B, thereafter, as shown in FIG. 4C, the axleassembly 10 can be dismantled only by pulling it out of the hub and theshaft mounting portion 3B.

As described in the above explanations, because the axle assembly 10 ofthe present invention can be easily mounted and dismantled on forks byone touch without designing breach on the tubular body, it is possibleto obtain excellent installation strength.

FIG. 5 is a sectional view showing transformation embodiment of the axleassembly 10 related to the present invention.

In the transformation embodiment, taper surface 6 is designed on theedge of the penetrating hole 4 of both shaft mounting portions 3A and3B, and taper surface 24 is designed to surface-contact with the tapersurface 6 on flange parts 12B and 20 of both nipping and holding members12 and 19. Accordingly, in a state that the axle assembly 10 is mountedonto both shaft mounting portions 3A and 3B, because the taper surface 6contacts with the taper surface 24, it is possible to more raise thestrength of installation.

In the above embodiment, the fastening bar 16 is moved through using thecam lever 14, however, instead of the cam lever 14, it is possible tofurnish a rotatable operating section on one end of the tubular body 11,to screw the fastening bar 16 into the operating section and to move thefastening bar 16 by a rotation operation of the operating section.

Further, instead of the above-mentioned coil spring 17, a spring sectionmay also be furnished on the guide block 18.

Furthermore, it is possible to integrate the bottoms of plural partitionpieces 19 a in the nipping and holding member 19 so as to leave out theguide block 18.

1. An axle assembly having a tubular body whose both ends are insertedinto respective penetrating holes formed on a pair of shaft mountingportions, and rotatably supports wheel hub, comprising: a nipping andholding means that is installed on one end of the tubular body and isused for pressing edge of the penetrating hole of the shaft mountingportion on one side; a fastening bar that passes through the nipping andholding means and is placed inside the tubular body; a moving means thatis placed to face to the nipping and holding means, is connected to oneend of the fastening bar, and makes the fastening bar move inside thetubular body towards one end of the tubular body; a nipping and holdingmeans with collet shape that has plural partition pieces and protrudesfrom other end of the tubular body so as to make the plural partitionpieces can expand and shrink diameter; a pressing means that isconnected to other end of the fastening bar, presses the nipping andholding means with collet shape by movement of the fastening bar, andpresses the respective partition pieces to edge of the penetrating holeof the shaft mounting portion on the other side; and a diametershrinking means that is installed on the pressing means so as to enableto move towards the other end of the tubular body, and couples with theplural partition pieces by moving so as to shrink diameter.